The analysts are in the field of "knowledge". Intelligence refers to knowledge and the types of problems addressed are knowledge problems. So, we need a concept of work based on knowledge. We need a basic understanding of what we know and how we know, what we do not know, and even what can be known and what is not known. The analysis should provide a useful basis for conceptualizing intelligence functions, of which the most important are "estimation" and "prediction". The intelligence itself, in its basic form, has a decision-making function. Intelligence analysis applies individual and collective cognitive methods to assess data and test assumptions in a secret socio-cultural context.